Coordinated response to imported vaccine-derived poliovirus infection, Barcelona, Spain, 2019-2020

In 2019, the Public Health Agency of Barcelona, Spain, was notifi ed of a vaccine-derived poliovirus infection. The patient had an underlying common variable immunodefi ciency and no signs of acute fl accid paralysis. We describe the ongoing coordinated response to contain the infection, which included compassionate-use treatment with pocapavir

Gut microbiota trajectory in early life may predict development of celiac disease.

BACKGROUND: To investigate whether alterations in the developing intestinal microbiota and immune markers precede celiac disease (CD) onset in infants at familial risk of developing the disease. METHODS: A nested case-control study was carried out as part of a larger prospective cohort study, which included healthy full-term newborns (> 200) with at least one first relative with biopsy-verified CD. The present study includes cases of CD (n = 10) and the best-matched controls (n = 10) who did not develop the disease after 5-year follow-up. Fecal microbiota, assessed by high-throughput 16S rRNA gene amplicon sequencing, and immune parameters were profiled at 4 and 6 months of age and related to CD onset. RESULTS: The microbiota of infants who remained healthy showed an increase in bacterial diversity over time, characterized by increases in Firmicutes families, but not those who developed CD. Infants who subsequently developed CD showed a significant reduction in sIgA levels over time, while those who remained healthy showed increases in TNF-α correlated to Bifidobacterium spp. An increased relative abundance of Bifidobacterium longum was associated with control children while increased proportions of Bifidobacterium breve and Enterococcus spp. were associated with CD development. CONCLUSION: The findings suggest that alterations in the early trajectory of gut microbiota in infants at CD risk could influence the immune maturation process and predispose to CD, although larger population studies are warranted to confirm this hypothesis

COVID-19 infection in first trimester of pregnancy marked by a liver cytolysis in a woman previously treated by hydroxychloroquine for repeated implantation failure : a case report

In December 2019, a new disease (COVID-19) caused by a novel coronavirus called SARS-CoV-2 emerged in China and spread to many other countries. There is only limited data about the clinical features of COVID-19 during pregnancy, especially in first trimester. We report a COVID-19 infection in a 35 years-old patient in first trimester of pregnancy and its consequent medical care. At 7 weeks of pregnancy, the patient, who did not have any pregestational comorbidities, complained of intense nausea and asthenia. An important liver cytolysis was discovered with biological perturbations of transaminases levels. No respiratory symptoms were recorded. Classical viral aetiologies and drug-related toxicity were discarded. Because of the aggravation of the symptoms and the occurrence of the breathlessness, the patient was tested for the COVID-19 in a nasopharyngeal swab. The RTq-PCR assay indicated the presence of SARS-CoV-2 RNA. In the absence of severe symptoms, the patient was monitored at home according to the French government guidelines. After a few days, the symptoms resolved without any complications. The pregnancy is still ongoing without any visible sequelae on the foetus so far. This first case illustrated the difficulty of COVID-19 diagnosis in patients with isolated digestive symptoms in first trimester of pregnancy that could be confused with gravida hyperemesis. Monitoring of pregnancy after an episode of COVID-19 should be strengthened with bimonthly foetal growth ultrasounds and doppler assessments because of the risks for intrauterine growth restriction. Comprehensive data on larger numbers of first trimester gravid women with COVID-19 are required to better understanding the overall impact of SARS-CoV-2 on maternal and birth outcome

Activation-induced deaminase is critical for the establishment of DNA methylation patterns prior to the germinal center reaction

Activation-induced deaminase (AID) initiates antibody diversification in germinal center B cells by deaminating cytosines, leading to somatic hypermutation and class-switch recombination. Loss-of-function mutations in AID lead to hyper-IgM syndrome type 2 (HIGM2), a rare human primary antibody deficiency. AID-mediated deamination has been proposed as leading to active demethylation of 5-methycytosines in the DNA, although evidence both supports and casts doubt on such a role. In this study, using whole-genome bisulfite sequencing of HIGM2 B cells, we investigated direct AID involvement in active DNA demethylation. HIGM2 naive and memory B cells both display widespread DNA methylation alterations, of which similar to 25% are attributable to active DNA demethylation. For genes that undergo active demethylation that is impaired in HIGM2 individuals, our analysis indicates that AID is not directly involved. We demonstrate that the widespread alterations in the DNA methylation and expression profiles of HIGM2 naive B cells result from premature overstimulation of the B-cell receptor prior to the germinal center reaction. Our data support a role for AID in B cell central tolerance in preventing the expansion of autoreactive cell clones, affecting the correct establishment of DNA methylation patterns